Notes from Main Injector/Recycler Group Meeting Monday, 7 October 2002 Bruce C. Brown Cons Gattuso -- RR Aggregate Development In addition to the other aggregate developments which are refining new RR procedures, Cons has developed a new SA (secondary application) tied to the sequencer which provides a visual representation of the recycler manipulations in the form of a flow chart. This display should help users to understand what their current condition is and what options are provided to proceed. Other new efforts include setting plot axes to match current conditions (especially intensities). The aggregates under development only control RR devices so MI or other device changes must be coordinated properly. Krish Gounder -- Results of Recent Scraping Studies There recently have been several opportunities to make measurements with the beam scraper system. These have included 1) Hor scrape of not-so-well cooled pbars sigma ~3.5 mm (no MI Ramps) 2) Ver scrape of well cooled pbars w/ top jaw sigma ~1.56 mm (emitt = 2.8 pi-mm-mr) IPM measurement before scrape gave 5.6 pi-mm-mr but it is believed that there is a x2 calibration difference. 3) Horiz scrape of well cooled pbars w/ wall jaw sigma ~1.55 mm (emitt = 2.73 pi-mm-mr) 4) Proton scrape with MI Ramping sigma ~2.79 mm (emitt = 8.94 pi-mm-mr) 5) Pbar scrape after big pbar store had data collection problems Analysis by digitizing picture from e-log gave sigma ~2.35 mm (emitt = 6.7 pi-mm-mr) A preliminary version of the MI Note in preparation on this is available: http://www-ap.fnal.gov/~bcbrown/MtgNotes/KG_MINote_on_Scraper_Profiles_021011.pdf and has been put into the document database as http://beamdocs.fnal.gov/cgi-bin/DocDB/ShowDocument?docid=377 Brajesh Choudhary -- BPM efforts with Digital Receiver Cards In addition to the BLT (beam line tuner) efforts using the digital receiver cards, there are now 4 channels available for use with the BPM software. The DSP software filters for a 2.5 MHz signal which it processes into a sine-like and a cosine-like term which are then combined to provide position signals. At present, the intensity does not get back to the rest of the software system. Four channels are currently available with four additional channels to be provided very soon. On the study day being reported, the current RR bpm system provided an RMS error on position of .09 - .16 mm. New cards gave an RMS error of .01 to .028 mm. Measuring the response to a local 3-bump (calculated using the design lattice properties), one observed Horiz Bump Measured -4.95 mm motion Calculated -4.65 mm motion. Vert Bump Measured 4.65 mm motion Calculated 2.99 mm motion. Shekhar -- Short Term Plans Try to have several pbar transfers to get 200 mA in RR, then extract to MI and accelerate to 150 GeV. Consider getting transfers on both Saturday and Sunday which net 50 E10 each, then more on Monday. Chandra Bhat & Bruce Brown -- PBar acceleration Still need to work on our kludge for a momentum jump when going to the MI. To permit easy development of this, a new $2E ramp has been developed. It manipulates the MI magnet current to provide an independent reset within the ramp so that the hysteretic field which is achieved can be controlled by modifying both the injection current and the reset current. This ramp is currently structured as follows: Nom Inj Cur => 40 GeV => Reset Cur => Pbar Inj Cur => 150 GeV